In various types of intraocular surgery, the degree of damage done to the corneal endothelial cells is a determining factor in assessing the success of the surgery. In particular, the air in the anterior capsule and the posterior capsule of the iris should be separated during intraocular surgery, in order to avoid reducing the success rate of the surgery due to air circulation. Furthermore, displacement of the vitreous should be avoided in order to prevent the vitreous from remaining in the anterior capsule and permanently damaging the anterior capsule tissues. Moreover, in cataract surgery, it is important to prevent shards of the crystalline lens from shifting during surgery, in order to avoid the need for a second surgery to repair the results of the shards of the crystalline lens having fallen into the posterior capsule.
A method is currently being used for preventing the corneal endothelial cells from being damaged, preventing air from entering the anterior capsule, preventing the posterior capsule of the iris from flowing, and preventing the vitreous or shards of the crystalline lens from shifting. The current method includes injecting injectable gel-like ocular viscoelastic devices (OVDs) into the intraocular tissues and then removing the ocular viscoelastic devices. The ocular viscoelastic devices, which have a gel-type structure similar to that of the vitreous, are also known as artificial vitreous. The ocular viscoelastic devices have characteristics that make them easy to adhere to the surface of the corneal endothelial layer, easy to separate from the intraocular tissues, convenient to inject, and easy to remove. However, there are risks to using the ocular viscoelastic devices in cataract surgery case, including: (1) insufficient protection and separating properties; (2) it is not easy to determine the location of the ocular viscoelastic devices and/or to determine whether the ocular viscoelastic devices remain in the intraocular tissues: (3) the ocular viscoelastic devices can easily become lost or taken away by drainage equipment; and (4) it is difficult to construct a complete plane barrier using ocular viscoelastic devices.
Therefore, the membrane for protecting the corneal endothelial cells should have the following characteristics: (1) they should be one-piece, resulting in being implanted or removed conveniently; (2) they should have a clear boundary, resulting in being able to conveniently determine the location of the membrane; (3) they should have high transparency, so that the membrane does not impact surgical use; (4) they should be soft and malleable; and (5) they should be tougher than ocular viscoelastic devices.
Accordingly, a novel transparent membrane for protecting the corneal endothelial cells and the intraocular tissues which overcomes the above difficulties and inconveniences is desired.